I wrote him a letter to show my ___ of his thoughtfulness.

问题描述:

I wrote him a letter to show my ___ of his thoughtfulness.
I wrote him a letter to show my ___ of his thoughtfulness.
A:achievement B:agreement C:attention D:appreciation
为什么?整句怎么翻译?

我给他写信以表达我对他体贴的感谢.
abc 意义不符,主要要理解his thoughtfulness 的意思